hone to

In his entertaining and enviably well-written book The Power of Babel, John
McWhorter writes (pp. 127-8), "Celtic languages have marched to the beat of
their own drummer to this extent because they have not been constrained by
contact with the other languages into honing to certain patterns." I've
seen plenty of "hone in on", attributed by MW Dictionary of English Usage to
George Bush during his '79-80 primary campaign against Reagan. However,
McWhorter's "hone to" doesn't sound like this or like anything else I've run
into. Any one else have anything on this usage?
Herb